Flexible coupling for tubes



Sept. 30, 1947. CHAVAYDA 2,428,143

FLEXIBLE COUPLING FOR TUBES Filed Jan. 22, 1945 Patented Sept. 30, 1947 Joseph J. Chavayda, Cleveland, Ohio, assignor to The Parker Appliance Company, Cleveland, 'Ohio, a corporation of Ohio Application January 22, 1945, Serial No. 573,942

. l 2 Claims. (Cl. 285-90) The invention relates to new and useful im provements in a coupling for tubes and more particularly to a coupling wherein the tube is secured to the coupling by deformable gasket members so that vibrations imparted to the tube will be absorbed by the gasket members.

An object of the invention is to provide 'a coupling of the above type wherein the gasket members are spaced from each other so as to receive therebetween an enlargement in the tube whereby pull-out strains on the tube are resisted by one of the deformable gaskets and the sealing efliciency of the other deformable gasket is not interfered with.

In the drawings the figure is a longitudinal sectional view through a. coupling embodying the improvements with the coupling in closed condition.

The coupling as illustrated includes a body member I having a usual bore 2 therethrough which boreis of substantially the same diameter as the inner diameter of the tube which is to be joined to the coupling. The body member is provided with a counter-bore 3 which is slightly larger in diameter than the outer diameter of the tube so that when the inner end of the tube extends intothecounter-bore, it is still out'of contact with the walls thereof. The end of the coupling member is cut away from the counterbore outwardly so as to provide an inclined tapered face 4 which -.is to serve as the inner wall for an annular recess for a sealing gasket. The nut 5 is secured to the body member I by a threaded connection 8. Said nut has an inwardly extending flange I provided with an opening 8 therethrough for the tube which is to be attached to the coupling, and it is indicated at 9. This opening 8 in the nut is of slightly larger diameter than the outer diameter of the tube. Between the end of the body member and the flange I of the nut there is an annular chamber H). In this chamber is located a sleeve II.

The tube 9 is provided with an enlargement l2 formed by beading the tube back from the end thereof. The sleeve II has an inner diameter in the region of said enlargement which is slightly greater than the external diameter of the enlargement so that this sleeve H does not contact with the tube. The sleeve II at its inner end I3 abuts against the end of the body member I and at the outer end It it abuts against the flange I when the coupling is closed. This limits the extent to which the nut can be turned onto the body member.

The sleeve is cut away so as to provide an arcuate. shaped wall I! which forms one side of an annular recess in which is placed a deformable ring gasket IS. The tube forms the third wall of this annular recess in which the gasket I6 is located. The sleeve is also provided at its other end the other side of the annular recess containing the deformable ring gasket l8 and the outer face of the tube forms the closing side of the recess. The ring gaskets I 6 and I8 are dimensioned so that when they are placed on. the tube they are distorted sufllciently so as to cause thering gaskets to make sealing contact with the tube,

In the assembly of the parts the nut is placed on the tube, then the ring gasket l8, and then the sleeve Ii. After the nut and gasket ill have been slipped onto the tube, the tube is beaded to provide the enlargement l2. The sleeve H is next slipped into the nut and the ring gasket it placed on the tube, after which the nut is turned onto the body member. This is the preferred method of assembling the parts, although this arrangement may be slightly varied, it being essential, however, that the nut be placed on the tube before the tube is headed to provide the enlargemerit I2.

The arcuate surface in the sleeve M are so dimensioned and positioned that when the nut is turned onto the body member the gasket I6 will engage the inclined seat 4 and provide a sealing contact between the gasket and the body member. The gasket is also slightly expanded when placed on the tube so that the sealing gasket will have a sealing contact with the tube and with the body member. The arcuate wall ll as shown in the drawings, is so dimensioned that when the coupling is closed the gasket is subjected to a slight pressure of the flange l on the nut. This pressure against the gasket will tend to deform the gasket so as to cause it to make a tight sealing contact with the tube and with the sleeve Hand also with the flange.

Any pull-out strains on the tube due to pressure on the line or otherwise will be resisted by the gasket it! which will be forced against the flange I and possibly be deformed so as to completely fill the recess in the outer end of the sleeve for the gasket. This will make a recess filled with a non-compressible fluid or deformable material which will positively resist the pulling strain on the tube. This resistance to the pull-out strains on the tube does not in any way affect or further deform the gasket it which remains in tight sealing contact with the body member and with the tube. These sealing gaskets are normally substantially circular-.in cross section and are deformed slightly when the coupling parts are assembled and the tube gri ped thereby.

It will be noted that the tube is held in the coupling solely through the contact of the sealing gaskets therewith and therefore the tube may flex under vibrations and the tube will not contact with the coupling members, but the vibrations will be absorbed by these deformable ring gaskets.

The arcuate faces of the sleeve H are substantially the same distance from the center plane of the sleeve. The ring gaskets when placed against these arcuate surfaces, project beyond the ends of the sleeve and when the nut is tightened, the gasket IE will be slightly deformed so as to establish a seal where it bears against the. end of the body member. The gasket is also sealed against the sleeve and the tube. The same is true of the gasket It! in its contact with the flan of the nut. The inner wall of the flange of the nut is at right angles to the longitudinal axis of the coupling while the wall 4 on the outer end of the body member is inclined. Therefore, when the coupling is closed the ringgasket l8 will be deformed to a slightly greater extent than the ring gasket l6. As already has been noted, when there is fluid pressure or other forces tending to pull the tube out of the coupling, the entire force is resisted by the ring gasket l8 without disturbing the ring gasket IB' which does the sealing. Also the ring gasket I8 is initially distorted to a greater extent than the ring gasket l6 and it will more effectively prevent outward movement of the tube. Fluid pressure on the line will also contact with the gasket l6 and deform it into tighter sealing contact with the tube, the sleeve and-the body wall. move outward a substantial amount before the gasket I8 is deformed suillciently to become a positive resistance to the pull-out action, the seal of the ring gasket It will not be disturbed because the arcuate surface l does not change its posi- 45 Even though the tube does 4 may be made without departing from the spirit of the invention as set forth in the appended claims.

I claim:

1. A coupling for a tube having an enlargement adjacent the end thereof comprising a body memher, a nut having a threaded connection thereto. and forming therewith an annular chamber, a sleeve rihssaid chamber dimensioned so as to be out of contact with the tube, said sleeve having annular recesses at the inner side of each'end which recesses are disposed on opposite sides of an enlargement in the tube secured to the coupling, a deformable ring gasket located in each recess, said gasket serving as the sole contact between the coupling and the tube when the coupling is closed.

2,. A coupling for a tube having an enlargement adjacent the end thereof comprising a body member, a nut having a threaded connection thereto, and forming therewith an annular chamber, a metal sleeve in said annular chamber abutting against the body member and the nut when the coupling is closed, the inner diameter of said sleeve being slightly larger than the diameter of an enlargement in the tube secured to the coupling, said sleeve having annular recesses at the inner side of each end, said recesses being disposed on opposite sides of said enlargement, a deformable ring gasket located in the recess at the outer end of said sleeve and dimensioned so as to project therefrom whereby the gasket is contacted with by the flange of the nut 'and deformed into tight sealing contact with the sleeve and the tube when the coupling is closed, and a deformable ring gasket disposed in said inner recess and dimensioned So as to project therefrom and contact with the body member when the coupling is closed so that the gasket is deformed into tight sealing contact with the tube, the sleeve and the body member, said nut, sleeve and body member being dimensioned so that the tube is contacted with solely by said deformable gaskets JOSEPH J. CHAVAYDA.

REFERENCES 'crrizn The following references are of record in the and this ensures a long life for the tube and the file of thi patent:

coupling parts in installations where there is flexing or vibrations of the tube of substantial magnitude.

It is obvious that minor changes in the details of construction and the dimensioning of the parts 56 2 UNITED STATES PATENTS Name Date Skinner at al. May 4, 1943 Howe Nov. 10, 1942 Number 

